I do give feedback in almost all cases where I am asked to complete a short survey.
I do also write reviews on Trustpilot and occasionally update them.
I have complained to my local borough council about a couple of things and they made a visit within two days and reported back to me with their findings.
I've also reported unsafe paving, kerbs and overhanging branches to the relevant departments at Guildford Council. They were, variously, inspected, marked repaired or cut down within 4 days.
I can't fault either Godalming TC, Waverley BC or Guildford Council for their continuing interest in keeping our boroughs safe, clean and in good order. Their flower displays are wonderful.
As for other companies such as utilities, I won a court case against British Gas re incorrect billing which they just would not admit to although I had solid proof.
Mind you, I've given very much more praise than made complaints.